bge driver not recognising BCM 5705M

I'm somewhat confused.  On a recent 5.1-CURRENT, boot -v gives me:

found-> vendor=0x14e4, dev=0x165d, revid=0x01
        bus=2, slot=0, func=0
        class=02-00-00, hdrtype=0x00, mfdev=0
        cmdreg=0x0116, statreg=0x02b0, cachelnsz=8 (dwords)
        lattimer=0x20 (960 ns), mingnt=0x40 (16000 ns), maxlat=0x00 (0 ns)
        intpin=a, irq=11
        powerspec 2  supports D0 D3  current D0

followed by:

pci2: <network, ethernet> at device 0.0 (no driver attached)

This is the internal Gigabit ethernet on my Dell D800 laptop... but
it's not recognised, even though...

static struct bge_type bge_devs[] = {

...

        { BCOM_VENDORID, BCOM_DEVICEID_BCM5705,
                "Broadcom BCM5705 Gigabit Ethernet" },

...

};

and ...

#define BCOM_VENDORID                   0x14E4
#define BCOM_DEVICEID_BCM5705M          0x165D

... so why doesn't the bge driver kick in?

[3:5:305]root_at_canoe:/usr/home/dgilbert> kldstat -v | grep bge
                29 pci/bge
                30 bge/miibus

Dave.

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|David Gilbert, Independent Contractor.       | Two things can only be     |
|Mail:       dave_at_daveg.ca                    |  equal if and only if they |
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